Automatic telephone system



Dec. 27, 1927. 1,653,790l

Y D. L. TEMPLE AUTOMATIC TELEPHONE SYSTEM Filed Deo. 29, 1925 ssheets-'sheet 1 Q m Q" gf L v \a I| di l;

- Bee; 27, 1927. 1,653,790.

D. L. TEMPLE AUTOMATIC TELEPHONE SYSTE Filed DGO. 29, 1925 3Sheets-SheffL 2 Patented Dec. 27, 1927. y 1,653,790

lUNITEDSTATES vPivriaziirr OFFICE. i

:DAVID L. TEMPLE, OF FLORAL PARK, NEW' YORK, ASSIGNR T0 WESTERN ELECTRICCOMPANY, INCORPORATED, OF NEWv YORK, N. Y., A CORPORATION OF NEW YORK.`

AUTOMATIC TELEPHONE SYSTEM.

p Application led December 29, 1925. Serial No. 78,184.

This invention relates to a simplified trunk or line circuits disclosedin Figs. 4, method of supervision in telephone systems or 6 by means ofthe cord circuit disclosed in but more particularly to cord circuits.Fig. 3. Figs. 1 and 2 are arranged to give 50 Heretoifore, supervisionhas been provided supervision on the answering end ot the 5 by means oflamps controlled by relays locord circuit in Fig. 3 and the trunk andline cated in the cord circuit under control of circuits of Figs. 4, 5and 6 are arranged to other relays in the trunl or line circuits withgive supervision on the calling end of the which the cord is used. Afeature of this in- `cord circuit. Jacks 315 and 316 are pro- 55 ventionis that the relays in the cord circuit vided for connectingan operatorstelephone 30 are eliminated and the supervisory lamps are headset tocord C. A

controlled by means of a double Wound A clearer conception oftheoperation and sleeve relay in either the trunk or line cirthe featuresof the invention maybe ob cuit, one Winding of which is shunted in andtained from the following detailed desciip- 60 out of circuit by theline relay, the shuntedl tion. vWhen a selector, such as isdisclosed inWinding being of such a resistance that the "the patent to R. L. StolelyNo. 1,474,008

lamp will be extinguished when the shunt is issued November 13, 1923,selects the trunk removed. circuit ST a circuit is closed from ground Itis the object of this invention to provide through the right Winding ofrelay 101, up- 65 improved vand simplified supervisory circuits per backcontact of relay 104, conductor 110, 2l for telephone exchange systems.through they selector, back over conductor A feature of this inventionis the use of a 111, lower bacl; contact of relay 1041 to bats toneunderthe control of a cord circuit key Vtery through the left `Winding ofrela-y 101. to notify the operatorthat the called sub- Relay 101operates and closes an obvious cir 70 scriber has answered and that thekey has cuit for relay 102. Relay 102 operated lights not been released.lamp 121 over a circuit from battery through A clear conception ott-heinvention may be the outer right front. contact of relay 102. had Vtromthe drawings and description in inner left back contact of relay 105,`to which: Y ground through lamp 121. Relay 102 also Fig. 1 discloses atrunk circuit incoming connects tone current from source `123 fromselector bank arranged for coin collect through lamp 106, right backcontact of reand refund. lay 105, inner right frontI contact of relay102 Fig. 2 discloses a trunk circuit incoming to conductor 111 andthence over the ring "from a connector bank. side of the line to thecalling subscribers Fig. 3 shows an operators cord circuit line. Relay102 at its lett contact alsok embodying the teaturesot this invention.`grounds the sleeve conductor 112 of the Fig. 4 shows a trunk circuitfor repeating trunlrto mark the trunk busy and holds the the pulses fromthe dial in the operators precedingselector switches operated. The cordcircuit to a selector circuit. operator, noting lamp 121 lighted,inserts the 85 Fig. 5 is a rural subscribers line circuit plug 320 oicord Cin the jack 120, thereby with common battery supervision. voperating relay 105 over a circuit from Fig. 6 discloses a ruralsubscribeus line ground through the windingsk of relay 105, circuit withmagneto supervision. sleeves of jack 120 and plug 320 to battery YThetrunk circuit disclosed in Fig. 1 is through lamp 321. The resistanceot the 90 used with a step-bystep selector circuit and 'windings ofrelay 105 in series is such that 15 is arranged for collection or refundoit coins lamp 321 will not light. `The operation of at the callingsubscribers station. This relay opens the circuit for lamp 121211:

trunk may he connected to any one et? the inner left contact and alsoriiioyes iik relay 309 in a manner Well known in the art.`

The `operation of relay 309 closes an obvious circuit through coil 312and the lettjvinding of tone coil 310 thereby giving the operator a busyclick in her headset which is plugged up in the jacks 315 and 316.` Y

lNe will assume, however, that the trunk `DT is idle. The operator theninserts the plug 330` into joel; 410 therebyioperating relay 403, treinbattery through lamp 331,

sleeves of plug1330 and jack 410l through the right Winding of relay 403to ground on the back contact ol relay 405. The operation of relay 403closes a circuit for operating relay 404 i'roin ground on the lettcontact or' relay 403, outer right norinal Contact ot relay 402, tobattery through the winding of relay 404.

The trunk circuit DT is non7 `in lcondition tor Y dialing. The operatorthrows dialing key 303 and connects conductors 317 and 313 to the tipandring leads, respectively, of the cord circuit. Relay 401 is alsooperated `ove a circuit 'troni ground on Contact `322 fof dial 306,conductor 317, inner upper alterv nate contact of key 303, tips of plug330 and jack 410, contact 417 of relay 412, contact Ll l) 419 of relay401, to battery through the Winding of? relay 401.V Relay 401 operatedcloses conductors 413 and 414 throughto conductors 420 and 421` whichVare connected to a :"atepby-"step selector (not`shown)'. Re lay 401locks under control` "of` relay 403 which is under control of the cordcircuit C. Relay 402 also operates at this time from ground throughresistance 327, outer lett contact ot relay 303, Yconductor 313,lowerinost alternate contact of key 303, rings of y'plug 330 andjaclf410, contact 413 of relay 412, to battery through the lettWindingot relay 402. The operation of relay 402 closes a new.operatingcircuit -for relay 404 from ground on contact- 322 oi dial 306,conductor 317, tips of cord 330'and jack 410, contact 417 ot relay 412,right outer front contact `021i relay 402, to battery through theWindingoi' relay 404,and short circuits at its lett contact Vthe relay405 thereby reducingl the impedance of the bridge across the trunkconductors. Y

lVhen the operator operates the dial 306, relay 404 .follows theimpulses and opens and closes a bridge across trunk conductors 420 and421 extending through contacts of relays 402 and 404. This in turncontrols the 0p- `scribcr has answered;

eration of the selector switch in a manner Well known in the art. lWhen`dial 306 was moved oli normal the alternate contact ol' spring 307 wasclosed thereby operating rclay 303 over a circuit trono battery throughthe lett winding ot relay 402, contact 413 of relay 412, rings of jack410 and plug 330, lower alternate contact ot' dialing lrcy 303,conductor 313, alternate contact of spring' 30T of dial 300 to groundthrough the righi` winding oi relay 303. Relay 303 operated, loclts inan obvious circuit to ground on the uppermost alternate contact of key303."` The operation of relay 303 disconnects resistance 327 `tronoconductor 313 and prepares an operating circuit for relay 313. Relay 313does not operate at this time as its ciri cuit is not complete. Upon thecompletion of dialing relay 402 deenergizes.

lllhen the desired line has been selected and the called subscriber hasanswered, re versed battery currentis transmitted `over trunk circuit420, 421 in a manner Well known in the art and polarizedrelay`405operates, in turn operating relay412 over an obrious circuit. Relay-412operated con neets conductors `413 und 414 through to the tip and ringrolf jack 410. Be- `tore battery was reversed in the selector cir cuit,V`ground was connected to conductor `420 and battery to conductor 421.`When the battery was reversed, the ground which is now connected toconductor 421 Willoperate relay 313, if the operator has not re storedthe dialing key 303. Relay 313opcrates over a circuit 'troni ground onconductor 421, lower contact` ot' relay 401, conductor 414, contact 410of relay 412, rings o1 jack 410 and plug 330, lower alternate contact ofkey 303, conductor 313, normal contact of spring 30T olf dial 30G, rightiront contact of relay 303 to battery through the Winding ot relay 313.The operation ot `rclay 313 connects a tone through coil .311, to theoperators headset notifying her that the dialin key 303 should berestored. Relay 313 releases `when the` dialing` hey is restored therebycuttingoli the tone. The operation of relay 405 also removes thc shuntfrom around the lett Winding oi? relay 403 thereby 1 inta-easing theresistance ot' the circuit tln'ough la1npl33l, and extinguishing thelamp aa anindication 'that the called? faul Sliouhl` the call be from acoin box line. the oiierator operates coin collect ltey" 113. Theoperation oll key 113 operatesrelay" 104 over an obvious circuit andconnects coin collect current to conductors 1l0 and 111., from coincollect source 116 through the winding oi relay 11T, lamp resistance110, alternate contact (dltey '113. through both aiernate contacta ofrelay 104 to conductors 110 and 111.

It the call for a party 'for which a charge is not to be made, there isno battery directly lll reversal over trunk circuit 420, 421. There`tore, lamp 331 `will remain lighted. When be refunded and refund key109 is Operated,

operating relay 1L over an ohviousclrcuit. Relay 101 connects coinrefund source 1111 through the Winding ot relay 113, lamp 108, alternatecontact ot' key 109, contacts oi relay 104. to conductors 110 and 111.

When the called subscriber replaces the receiver on the switchhool,relay l105 is released thereby connecting. a shunt around the" lettWinding of relay 40S, allowing lamp 331 to light as a disconnect signal.This. is only true on a call through a station for which a charge ismade. It the call is from a no-charge line, the operator listens in forthe subscriber to hang up at which time she withdraws plug 330 from jacl;r L110. The release ot relay L105 also opens the circuit ot relay411.2 vopening the talking conductors. lill/Then the operator withdrawsplug 3320 from jack 410, relay 403 also releases in turn releasing relay4101 and restoring the circuit to normal. When the calling subscriberreplaces the receiver on the sivitchhoolnrelay 101 releases. therebyconnecting a shunt around the right Winding ot relay 105 `trom ground`on the back Contact ot relay 101. This shunt removes resistance fromthe sleevecircuit and allows lamp 321 in the cord circuit to light as adisconnect signal. The release of relay 101 also opens the circuit 'torrelay 102 which releases and removes the busy ground from the sleeve112. The trunk circuit ST new restores to normal, releasing the selectorwhich extended the calling line into connection with the, trunk. y y

call incoming over `a trunk such as `CT troni a connector' circuit andoutgoing'to a coinnion battery line circuit ivill nent be considered.`fl/'hen a connector such as disclosed inthe patent to R. L. Stokelyabove referred to seizes terminals connected to conductors p 210, 211and 212, ringing current will be connected to relay 201 causing it tooperate and in turn operate relay 202 from ground on the inner contactof relay 201, lett contact of relay 201 to battery through the Winding`oit relay 202, Relay 202 is heldoperated to ground on the sleeveconductor 212 over its right front contact. lhe operation ot relay 202lights lamp 221 over fan obvious circuit. Lamp 221 is an indication tothe operator ol an incoming call. The operator then inserts plug 320into jack 220 which is associated with lamp 221 thereby operating relay204; over a circuit from battery through lamp 321, sleeves of jack 220and plug 320, lett Winding ol" relay 20e to ground on the baci; contactot relay 203 and the outer front contact of relay 201. The right Windingof `ductors 520 and 521.

relay 204 is shunted by ground on theback Contact ot' `relay 203;Theoperation of relay 204 connects relay 203 across conductors 210 and211 thereby operating the ringing trip relay in the connector. rEheremoval of ringing current releases relay 201 andoperates relay 203 trombattery in the connector. 'lhe operation ot relay 203` and the releaseot relay 201 removes the shunt from around the right Winding ot relay2041 thereby extinguishing lamp 321. Relay 204 also connects holdingground to conductor 212 over the hack contact ot relay 202and the innerfront contact o1"- relay 20a, for the purpose ot holding the connector.y 1

The operation ol cord circuit G is the saine as described above untilplug 830 is inserted in jack 510. llt this time, relay 503 Will operatefrom battery through lamp 831, sleeves oic plug 330 and jack 510, lettWinding of relay 503 to ground at the right contact of relay 502. Relay508 operates and f lamp 331 lights Ringing current and ground areconnected to the tip and ring of cord C by the operation ot' ley 30d,and relay 504 operates in turn operating relay 505 which cuts the linerelay 501 oli1 of the line. The ringing current also rings the bell atthe called station.

'lr/'heu the operator releases the ringing hey 'B0-1 relay 504 releasesrestoringl relay 505 which connects line relay 501 across conl/Vhen thecalled suhscriher at station 5112 answers, relay 501 operates frombattery through its lett Winding, right bach Contact ot relay 505,conductor 521, subscribers station 512, conductor 520. lett back contactot relay to ground through the right windingot relay 501. litelay501Joperated, operates relay 502 over an obvious circuit. The operationci relay 502 removes 'the shunt troni around the right Windingl oi relay503 extinguishing lamp 331 as an indication that the subscriber hasanswered. Should the subscriber flash the switchhoolr. relay 501 willfollow the switch hook in turn operating and releasingrelay 502 `whichwill open and close the shunt around the right Winding ot relay 503,causing lamp 331 to flash as a signal to the operator.

When the called party replaces the -receiver on the sivitchhook, relay501 will release in turn releasing relay 502 Which Will replace theshunt around the right Winding of relay 503 causing lamp 331 to light asa disconnect signal. When the operator with* draf's plug 330 from jack510. relay 503'ivill release and restore the circuit to normal.

`When the calling subscriber replaces the receiver on the sivitchhook,the intervening switches will release except the connector which remainsoperated until the operator withdraws'plug 320 from jack 220 opening thecircuit of relay 204. The releasevot relay 204 opens the circuit forrelay 203 and releases the connector.

Ironia call from a toll board the toll opi Tof trunks ST or GT throughthe cord C to the magneto linek circuit ML. The operation of the twotrunks and the cord circuit is the same as described above until plug330is inserted in`jack 610. At this time relay 602 operates from batterythrough lamp 331.

sleeve of plug 320, sleeve oi j ack 610, wind;

ings of relay 602 to ground. Lamp 331 does not light but relay 602operates. The operator now operates ringing key 304: which closes acircuit from ground on its upper alternate contact, upper normal contactof dial key 303, tips of plug 330 and jack 610, winding of relay 601,rings of jack 610 and plug` 330, lower normal contact of dial key 303,the lower normal Contact of key 3041 to ringing source 302. Relay 601operates and places a shunt across the right winding of relay 602allowing lanip 331 to light.. The operator after ringing the calledsubscriber releases the ringing key and throws the talk ing key 305. tolisten for the response of the called subscriber. When the ringing keyis released, relay601 is releasedin turn removing the shunt from aroundthe right winding of relay 602 extinguishing lamp 331. `ihen the calledsubscriber rings oit", relay 601 again operates shunting the left winding of relay 602, causing lamp 331 to light asv an indication to theoperator that the called party has disconnected. When the plug 330 isremoved from jack 610, the operated relays release yrestoring thecircuit to normal.

`When the subscriber at substationv 512 initiates a call, relay 501operates over the back contacts oi cut-ott relay 505 and the line loopand. closes an obvious circuit for relay 502. Relay 502 in turn closes acircuit over its lett contactand the back contact of relay 503 for lamp511. noting the illumination of lamp 511 inserts plug 320 in jack 510thereby causing the operation ot' relay 503 in series with lamp 321.Relay 503 operating opens the circuit ot lamp 511 extinguishing it.Since relay 502 is` at the time energized the shuntaround the rightwinding of relay 503 is open and the full resistance of relay 503 isinserted in the circuit of lamp 321 whereby lamp 321 is not lighted.

It' the subscriber at station 622 initiates a call by operating hismagneto, relay 601 operates closing a circuit for relay 603 from Theoperator `neaefrco battery contact of relay 602, winding of re-` lay603to ground at the left contact of re lay 601. Relay 603 upon operatinglocks to ground over its right Contact and at its left contact closes acircuit for lighting lamp 611, extending from battery at the contact ot`relay 602, left contact ot relay 603 to ground through lamp 011.` The`operator noting the illumination oi lamp 611 inserts plug 320 in jack610 thereby causing `the operation otrelay 602 in series with lamp 321.Relay 602 operating opens the circuits oi relay 603 and lamp 611. Lamp321 does not light, as following the release of rela 601 when thesubscriber ceases ringing, bot windings of 'relay 602 are inthe circuitof lamp 321.

W'hat is claimed is:

1. In a telephone system, a cord circuit, a

aline, a signal lamp ij'or said line, a ring down relay for said line, adouble wound cut-utf relay, a third relay controlled by said ring downrelay, a circuit for said lamp extending through contacts of andcontrolled by said cut-oil' relay and said third relay, a supervisorylamp in said cord circuit, a circuit for said latter lamp extendingthrough both windings ot' said cut-oil relay, the resistance ot' saidwinding being such that said supervisory lainp does not light, and ashunt for one winding of said cut-oii relay controlled by said ring downrelay whereby said supervisory` lamp becomes lighted.

2. In a telephone system, a cord circuit, a line, a ring down relay forsaid line, a double wound cut-oli' relay, a supervisory lamp in saidcord circuit, a circuit for said lamp yextending through both windingsof said cut-oit relay, the resistance of said windings beingsuch thatsaid lamp does not light, and a shunt adapted to be closed through acontact of said ring down relay for shunting one winding of saidcut-oil' relay Whereby said lamp becomes lighted.

3. In a` telephone system, a cord circuit, an operators telephonecircuit, a called line, a key, a tone source for indicating to theoperator the failure to release the key after the called station hasanswered, a relay under control of said key for connecting said tonesource to said operators circuit, and means under control ot the calledstation for causing the operation of said relay until said key hasbeenreleased. y

4. In a telephone system, a cord circuit, an operators telephonecircuit, a called line, a key in said cord circuit, a tone source forindicating that the key has not been released after the called stationhas answered, a relay under control of said key, and a second relayunder control of the called station and of said iirst relay unless saidkey has been released for connecting said tone to said op eratorscircuit.

the joint control of said key and of said apparatus for connecting saidtone source to 10 said operators circuit.

n Witness whereof, I hereunto subscribe my name this 26th clay ofDecember, A. D. 1925.

DAVID L. TEMPLE.

